Which digestive structure is NOT correctly paired with its secretions? a. Brush border cells of the small intestine: Aqueous salt and mucus mixture b. Liver and pancreas: Bicarbonate ions c. Liver: Bile d. Pancreas: Digestive enzymes e. Brush border cells of the small intestine: Digestive enzyme

b. Liver and pancreas: Bicarbonate ions

Explanation:

In order to answer the question, we need to review various organs of alimentary canal and their secretions.

Salivary glands produce saliva which contains Salivary amylase and acts upon starch.

Stomach produces hydrochloric acid (HCl) and gastric juice (contains pepsin).

Liver produces bile and is responsible for emulsification (breakdown) of fats.

Pancreas is a complicated organ having both endocrine and exocrine functions.

Exocrine secretion includes pancreatic juice which contains enzymatic component (digestive enzymes) and aqueous component (bicarbonate ions).

Brush border of small intestine produces bicarbonate-rich alkaline mucous and digestive enzymes. Mucous protects against the irritating effects of acidic secretions and digestive enzymes aid in breaking down molecules.

Coming back to the question,

b. liver and pancreas: Bicarbonate ions

is the answer as liver is not responsible for Bicarbonate (HCO₃⁻) ions secretion.